I need help finding a manga!

So, in the story the uke and seme (older) are dating and used to attend the same high school. The uke had always had a crush on the seme, but believed that the seme was dating his best friend. In College, they get together. But the uke becomes insecure about their relationship, believing that the seme has gotten back together with the friend, and decides to leave, leaving a ring behind.

I apologize if the description is vague. Any help would be appreciated!
Thank you.(￣∇￣")